Inferring a weighted elastic network from partial unfolding with coarse-grained simulations

Proteins. 2014 Jan;82(1):119-29. doi: 10.1002/prot.24381. Epub 2013 Sep 10.

Abstract

A number of studies have demonstrated that simple elastic network models can reproduce experimental B-factors, providing insights into the structure-function properties of proteins. Here, we report a study on how to improve an elastic network model and explore its performance by predicting the experimental B-factors. Elastic network models are built on the experimental Cα coordinates, and they only take the pairs of Cα atoms within a given cutoff distance rc into account. These models describe the interactions by elastic springs with the same force constant. We have developed a method based on numerical simulations with a simple coarse-grained force field, to attribute weights to these spring constants. This method considers the time that two Cα atoms remain connected in the network during partial unfolding, establishing a means of measuring the strength of each link. We examined two different coarse-grained force fields and explored the computation of these weights by unfolding the native structures.

Keywords: B-factor; GNM; WCN; normal mode analysis; pfGNM; vibrational dynamics.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms*
  • Azurin / chemistry
  • Cyclophilin A / chemistry
  • Cytochromes c / chemistry
  • Models, Chemical*
  • Molecular Dynamics Simulation*
  • Oligopeptides / chemistry
  • Plant Proteins / chemistry
  • Protein Folding*
  • Proteins / chemistry*
  • Ribonucleases / chemistry
  • Temperature
  • Ubiquitin / chemistry

Substances

  • Oligopeptides
  • Plant Proteins
  • Proteins
  • Ubiquitin
  • Azurin
  • N-(3-N-(benzyloxycarbonyl)amino-1-carboxypropyl)leucyl-O-methyltyrosine N-methylamide
  • crambin protein, Crambe abyssinica
  • Cytochromes c
  • Ribonucleases
  • ribonuclease Sa3
  • Cyclophilin A